Application of 18F-PSMA-1007 PET/MR Imaging in Early Biochemical Recurrence of Prostate Cancer: Results of a Prospective Study of 60 Patients with Very Low PSA Levels ≤ 0.5 ng/mL.

The use of 18F-PSMA-1007 and the role of PET/MR in the diagnosis of prostate cancer are not conclusively confirmed. There are reports indicating the potential pros and cons of using 18F-PSMA-1007 as well as the PET/MR technique in prostate cancer recurrence, but they are not yet included in the EAU guidelines. The aim of the study was to assess the effectiveness of 18F-PSMA-1007 PET/MR in detecting BCR lesions at very low PSA levels <0.5 ng/mL. METHODS: Sixty patients with BCR after radical prostatectomy (RP) with PSA ranged 0.1-0.5 ng/mL were enrolled in a prospective study. All patients underwent simultaneous whole-body and pelvic 18F-PSMA-1007 PET/MR. The obtained results were verified by 12-month follow-up. RESULTS: Fifty-three lesions were detected in 45 patients with 75% detection rate. The mean PSA value was 0.31 ng/mL. Of all PSMA-positive foci, 91% were localized in the pelvis, and only 9% of lesions were located in the extrapelvic region. Local recurrences were detected in 29%, PSMA-positive lymph nodes were detected in 64% of patients and bone metastases lesions were detected in 7% of patients. CONCLUSIONS: 18F-PSMA-1007 PET/MR seems to be an excellent diagnostic tool in patients with early BCR with very low PSA levels, especially with dt PSA < 6 months. The synergistic effect of combining 18F-PSMA-1007 and whole-body PET/MR with precise multiparametric assessment of pelvic lesions is of particular benefit in early BCR.

Changes in plasma endocannabinoids concentrations correlate with 18F-FDG PET/MR uptake in brown adipocytes in humans.

Introduction: Recent data suggest a possible role of endocannabinoids in the regulation of brown adipose tissue (BAT) activity. Those findings indicate potential treatment options for obesity. The aim of this study was to evaluate the relationship between plasma endocannabinoids concentrations and the presence of BAT in humans. Methods: The study group consisted of 25 subjects divided into two groups: BAT positive BAT(+), (n = 17, median age = 25 years) and BAT negative BAT(-), (n = 8, median age = 28 years). BAT was estimated using 18F-FDG PET/MR after 2 h of cold exposure. The level of plasma endocannabinoids was assessed at baseline, 60 min and 120 min of cold exposure. Results: In both groups, BAT(+) and BAT(-), during the cooling, we observed a decrease of the same endocannabinoids: arachidonoylethanolamide (AEA), eicosapentaenoyl ethanolamide (EPEA) and oleoyl ethanolamide (OEA) with a much more profound decline in BAT(+) subjects. Statistically significant fall of PEA (palmitoylethanolamide) and SEA (stearoylethanolamide) concentrations after 60 min (FC = 0.7, p = 0.007 and FC = 0.8, p = 0.03, respectively) and 120 min (FC = 0.81, p = 0.004, and FC = 0.9, p = 0.01, respectively) of cooling was observed only in individuals with BAT. Conclusion: We noticed the profound decline of endocannabinoids concentrations in subjects with increased 18F-FDG PET/MR uptake in BAT. Identification of a new molecules related to BAT activity may create a new target for obesity treatment.

Exploration of oxidized phosphocholine profile in non-small-cell lung cancer.

Introduction: Lung cancer is one of the most frequently studied types of cancer and represents the most common and lethal neoplasm. Our previous research on non-small cell lung cancer (NSCLC) has revealed deep lipid profile reprogramming and redox status disruption in cancer patients. Lung cell membranes are rich in phospholipids that are susceptible to oxidation, leading to the formation of bioactive oxidized phosphatidylcholines (oxPCs). Persistent and elevated levels of oxPCs have been shown to induce chronic inflammation, leading to detrimental effects. However, recent reports suggest that certain oxPCs possess anti-inflammatory, pro-survival, and endothelial barrier-protective properties. Thus, we aimed to measure the levels of oxPCs in NSCLC patients and investigate their potential role in lung cancer. Methods: To explore the oxPCs profiles in lung cancer, we performed in-depth, multi-level metabolomic analyses of nearly 350 plasma and lung tissue samples from 200 patients with NSCLC, including adenocarcinoma (ADC) and squamous cell carcinoma (SCC), the two most prevalent NSCLC subtypes and COPD patients as a control group. First, we performed oxPC profiling of plasma samples. Second, we analyzed tumor and non-cancerous lung tissues collected during the surgical removal of NSCLC tumors. Because of tumor tissue heterogeneity, subsequent analyses covered the surrounding healthy tissue and peripheral and central tumors. To assess whether the observed phenotypic changes in the patients were associated with measured oxPC levels, metabolomics data were augmented with data from medical records. Results: We observed a predominance of long-chain oxPCs in plasma samples and of short-chain oxPCs in tissue samples from patients with NSCLC. The highest concentration of oxPCs was observed in the central tumor region. ADC patients showed higher levels of oxPCs compared to the control group, than patients with SCC. Conclusion: The detrimental effects associated with the accumulation of short-chain oxPCs suggest that these molecules may have greater therapeutic utility than diagnostic value, especially given that elevated oxPC levels are a hallmark of multiple types of cancer.

Different Protein Sources Enhance 18FDG-PET/MR Uptake of Brown Adipocytes in Male Subjects.

BACKGROUND: The unique ability of brown adipocytes to increase metabolic rate suggests that they could be targeted as an obesity treatment. OBJECTIVE: The objective of the study was to search for new dietary factors that may enhance brown adipose tissue (BAT) activity. METHODS: The study group comprised 28 healthy non-smoking males, aged 21-42 years old. All volunteers underwent a physical examination and a 75 g oral glucose tolerance test (75g-OGTT). Serum atrial and brain natriuretic peptide (ANP, BNP), PRD1-BF1-RIZ1 homologous domain containing 16 (PRDM16) and eukaryotic translation initiation factor 4E (eIF4E) measurements were taken, and 3-day food intake diaries were completed. Body composition measurements were assessed using dual-energy X-ray absorptiometry (DXA) scanning and bioimpedance methods. An fluorodeoxyglucose-18 (FDG-18) uptake in BAT was assessed by positron emission tomography/magnetic resonance (PET/MR) in all participants after 2 h cold exposure. The results were adjusted for age, daily energy intake, and DXA lean mass. RESULTS: Subjects with detectable BAT (BAT(+)) were characterized by a higher percentage of energy obtained from dietary protein and fat and higher muscle mass (p = 0.01, p = 0.02 and p = 0.04, respectively). In the BAT(+) group, animal protein intake was positively associated (p= 0.04), whereas the plant protein intake negatively correlated with BAT activity (p = 0.03). Additionally, the presence of BAT was inversely associated with BNP concentration in the 2 h of cold exposure (p = 0.002). CONCLUSION: The outcomes of our study suggest that different macronutrient consumption may be a new way to modulate BAT activity leading to weight reduction.

PET/MRI-Evaluated Activation of Brown Adipose Tissue via Cold Exposure Impacts Lipid Metabolism.

Although brown adipose tissue (BAT) is considered to play a protective role against obesity and type 2 diabetes, the mechanisms of its activation and associations with clinical parameters are not well described. Male adults underwent a 2 h cold exposure (CE) to activate BAT and, based on the results of PET/MRI performed after the CE, were divided into BAT(+) and BAT(-) groups. During the CE procedure, blood samples were collected and alterations in plasma metabolome in both groups were investigated using LC-MS. Additionally, associations between clinical factors and BAT were examined. Moreover, levels of glucose, insulin, leptin, TNF-α, FGF21, and FABP4 were assessed in serum samples. In the BAT(+) group, levels of LPC(17:0), LPE(20:4), LPE(22:4), LPE(22:6), DHA, linoleic acid, and oleic acid increased during CE, whereas levels of sphinganine-phosphate and sphingosine-1-phosphate decreased. Levels of LPE(O-18:0), 9-HpODE, and oleic acid were elevated, while the level of LPE(20:5) was reduced in BAT(+) compared to BAT(-) subjects. AUCs of LPC(18:2), LPC(O-18:2)/LPC(P-18:1), and SM(d32:2) negatively correlated with BAT. In the BAT(+) group, the concentration of FABP4 during and after CE was decreased compared to the basal level. No alterations were observed in the BAT(-) group. In conclusion, using untargeted metabolomics, we proved that the plasma metabolome is affected by cold-induced BAT activation.

Assessment of Clinical Utility of Assaying FGF-23, Klotho Protein, Osteocalcin, NTX, and Sclerostin in Patients with Primary Hyperparathyroidism.

The purpose of this study was to assess the clinical usefulness of assaying the fibroblast growth factor (FGF-23), Klotho, osteocalcin, N-terminal telopeptide of type I collagen (NTX), and sclerostin levels in patients with primary hyperparathyroidism (PHPT) as markers of bone damage as well as for surgical treatment success. Seventeen patients with hypercalcemic PHPT and normal kidney function were studied. In all patients, PTH (parathormone), serum calcium, and creatinine were performed before and six months after parathyroidectomy (PTX). The studied group included patients whose PTH and calcium concentrations normalized post-operatively and with confirmed histopathological diagnosis. The control group consisted of nine age-matched healthy volunteers. The PHPT patients had elevated concentrations of FGF-23, osteocalcin, and NTX and reduced levels of sclerostin, as compared to the control group. After PTX, osteocalcin, NTX, and sclerostin levels normalized. The plasma values of FGF-23 decreased significantly, but remained higher than in healthy subjects. Serum Klotho protein levels did not differ significantly in the two groups. These results suggest that osteocalcin and NTX may potentially be considered as markers of PHPT progression. Additionally, serum normalization of osteocalcin, NTX, and sclerostin might be considered as indicators of PTX success. On the other hand, FGF-23 can represent a parameter reflecting the degree of calcium-phosphate imbalance in PHPT patients, but its usefulness in monitoring the effects of PTX requires further research. The clinical utility of assaying Klotho in PHPT remains to be confirmed.

Dosimetry during adjuvant 131I therapy in patients with differentiated thyroid cancer-clinical implications.

The activity of radioiodine (131I) used in adjuvant therapy for thyroid cancer ranges between 30 mCi (1.1 GBq) and 150 mCi (5.5 GBq). Dosimetry based on Marinelli's formula, taking into consideration the absorbed dose in the postoperative tumour bed (D) should systematise the determination of 131I activity. Retrospective analysis of 57 patients with differentiated thyroid cancer (DTC) after thyreidectomy and adjuvant 131I therapy with the fixed activity of 3.7 GBq. In order to calculate D from Marinelli's formula, the authors took into account, among other things, repeated dosimetry measurements (after 6, 24, and 72 h) made during scintigraphy and after administration of the therapeutic activity or radioiodine. In 75% of the patients, the values of D were > 300 Gy (i.e. above the value recommended by current guidelines). In just 16% of the patients, the obtained values fell between 250 and 300 Gy, whereas in 9% of the patients, the value of D was < 250 Gy. The therapy was successful for all the patients (stimulated Tg < 1 ng/ml and 131I uptake < 0.1% in the thyroid bed in follow-up examination). Dosimetry during adjuvant 131I therapy makes it possible to diversify the therapeutic activities of 131I in order to obtain a uniform value of D.

Pre-Processing Method for Contouring the Uptake Levels of [18F] FDG for Enhanced Specificity of PET Imaging of Solitary Hypermetabolic Pulmonary Nodules.

BACKGROUND: The paper presents a pre-processing method which, based on positron-emission tomography (PET) images of 18F-fluorodeoxyglucose ([18F] FDG) hypermetabolic pulmonary nodules, makes it possible to obtain additional visual characteristics and use them to enhance the specificity of imaging. MATERIAL AND METHODS: A retrospective analysis of 69 FDG-PET/CT scans of solitary hypermetabolic pulmonary nodules (40 cases of lung cancer and 29 benign tumours), where in each case, the standardised uptake value of the hottest voxel within the defined volume of interest was greater than 2.5 (SUVmax > 2.5). No diagnosis could be made based on these SUVmax values. All of the PET DICOM images were transformed by means of the pre-processing method for contouring the uptake levels of [18F] FDG (PCUL-FDG). Next, a multidimensional comparative analysis was conducted using a synthetic variable obtained by calculating the similarities based on the generalised distance measure for non-metric scaling (GDM2) from the pattern object. The calculations were performed with the use of the R language. RESULTS: The PCUL-FDG method revealed 73.9% hypermetabolic nodules definitively diagnosed as either benign or malignant lesions. As for the other 26.1% of the nodules, there was uncertainty regarding their classification (some had features suggesting malignancy, while the characteristics of others made it impossible to confirm malignancy with a high degree of certainty). CONCLUSIONS: Application of the PCUL-FDG method enhances the specificity of PET in imaging solitary hypermetabolic pulmonary nodules. Images obtained using the PCUL-FDG method can serve as point of departure for automatic analysis of PET data based on convolutional neural networks.

The Role of the CYP11B2 Promoter Polymorphism in the Diagnosis of Primary Aldosteronism.

BACKGROUND: nowadays, primary aldosteronism (PA) is suggested to be the most frequent cause of secondary hypertension and it reaches 10% of whole hypertensive population. The CYP11B2 promoter polymorphism might cause aldosterone overproduction. The aim of this study was to establish whether the polymorphism CYP11B2 promoter has a significant impact on diagnostic of PA. MATERIAL AND METHODS: study group consisted of 239 hypertensive patients previously diagnosed with adrenal incidentaloma. For diagnose of PA were performed: screening test-aldosterone-renin ratio (ARR) and saline suppression test (SIT) as a confirmatory test. Genotyping was carried out by the real time PCR method. The significance of differences between the groups was evaluated through Student's t-test. RESULTS: our study revealed that genotype TT had plasma aldosterone concentration (PAC), ARR and SIT significantly higher in comparison with CC patients. The mean PAC in CC was 12.71 ng/dL vs. 20.55 ng/dL in TT patients (p = 0.037), which consequently gave a higher ARR in TT patients (119 vs. 44, p = 0.034). Mean aldosterone concentration in SIT was 2.40 ng/dL in CC patients and 9.99 ng/dL in TT patients (p = 0.046). Patients with CC genotype required less hypotensive drugs in comparison with TT genotype (p = 0.044). PA was recognized in 16 patients. Nine patients had TC genotype, six TT, and one with CC genotype. CONCLUSION: our study revealed predisposing TT genotype to PA. Additionally, patients with TT genotype, regardless of the PA presence, had more severe hypertension. The determination of the CYP11B2 promoter polymorphism seems to be useful in the diagnosis of PA, especially in cases where it is difficult to properly prepare patients for hormonal tests or even results of the hormonal test are incoherent.

Enhancing the efficacy of 131I therapy in non-toxic multinodular goitre with appropriate use of methimazole: an analysis of randomized controlled study.

PURPOSE: It is possible to raise the rate of the uptake of 131I in the thyroid gland (RAIU) by increasing the endogenous TSH level through appropriate use of methimazole (MMI) prior to 131I therapy. The purpose of this paper is to assess the impact of pre treatment with MMI on the efficacy of 131I therapy in non-toxic multinodular goitre (NMG). METHODS: Thirty-one patients with NMG received 131I treatment in order to reduce the volume of the thyroid (TVR). Those in group 1 (n = 16) were administered 10 mg of methimazole for 6 weeks. Four days after its discontinuation, they received 131I. Patients in group 2 (n = 15) were given a placebo instead of MMI. The therapeutic activity of 131I was constant (800 MBq) and was repeated every 6 months. Treatment was discontinued when TVR reached <40 ml. RESULTS: In group 1, RAIU increased approximately twofold. Ten patients from group 2 and four patients from group 1 received further doses of 131I. The median of time until TVR decreased below 40 ml was 9 months [6-12 months] and 18 months [14-22 months] in group 2. At 2 years after the 131I therapy, the occurrence of hypothyroidism did not differ significantly (36% in group 1 and 33% in group2, p = 0.074). CONCLUSIONS: Radioiodine treatment of NMG preceded with appropriate application of MMI is efficient thanks to increased RAIU, shorter period of treatment, and lower frequency of 131I administration, without an increase in the incidence of post-treatment hypothyroidism.

PET/MRI-guided GTV delineation during radiotherapy planning in patients with squamous cell carcinoma of the tongue.

PURPOSE: The aim of the study was to evaluate the usefulness and accuracy of 18-fluorine-labeled fluorodeoxyglucose (PET) and magnetic resonance imaging (MRI) hybrid in gross tumor volume (GTV) delineation during radiotherapy planning in patients with carcinoma of the tongue. METHODS: Ten patients with squamous cell carcinoma (SCC) of the tongue underwent computed tomography (CT) and PET/MRI examination. The GTV for primary tumor and lymph nodes (nGTV) were defined on CT (GTV-CT) and compared to GTVs obtained from PET (GTV-PET) and MRI (GTV-MRI) images. Two methods of GTV determination were used: visual interpretation of CT, PET (GTV-PETvis) and MRI images and quantitative automatic method (Syngovia, Siemens) based on a chosen threshold value (20%, 30%, 40%, 50%) of standardized uptake values (SUVmax) from PET examination (GTV-PET20%, GTV-PET30%, etc.). Statistical analysis of differences in GTV values obtained from CT, PET and MRI studies was performed. GTV-CT was used as a reference. RESULTS: In all, 80% of GTV-MRI and 40% of GTV-PETvis were larger than GTV-CT. Respectively, 20% of GTV-MRI and 60% of GTV-PETvis were smaller than GTV-CT. Taking into account all threshold measurements, 70% of volumes were smaller than GTV-CT. GTV-PET30% were the most closely related volumes to GTV-CT from all threshold methods in 50% of patients. GTV-PETvis generated the most similar volumes in relation to GTV-CT from all PET measurements. Statistical analysis confirmed those results. Compared to nGTV-CT, 70% of nGTV-MRI and 20% of nGTV-PETvis were larger. The remaining nGTV-MRI and nGTV-PETvis measurements were smaller than nGTV-CT. Measurements of all thresholds nGTVs were smaller than nGTV-CTV in 52.5% of cases. nGTV-PET20% were the most closely related volumes to nGTV-CT in 40% of the cases. Statistical analysis showed that nGTV-PET20% (p = 0.0468), nGTV-PETvis (p = 0.0166), and nGTV-PET50% (p = 0.0166) diverge significantly from nGTV-CT results. nGTV-MRI (p = 0.1141), nGTV-PET30% (p = 0.2845), and nGTV-PET40% (p = 0.5076) were significantly related with nGTV-CT. CONCLUSION: Combination of PET/MRI provides more information during target tumor mass delineation in radiotherapy planning of patients with SCC of the tongue than other standard imaging methods. The most frequently matching threshold value was 30% of SUVmax for primary tumor delineation and 30-40% of SUVmax for nGTV determination.

Efficacy of 99mTc-DTPA SPECT/CT in diagnosing Orbitopathy in graves' disease.

BACKGROUND: The most frequently used methods of assessing Graves' orbithopathy (GO) include: Clinical Activity Score (CAS), ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI). There exists another, slightly forgotten, imaging method: single-photon emission computed tomography (SPECT) with the use of diethylenetriaminepentaacetic acid tagged with 99mTc (99mTc-DTPA). These days it is possible to conduct a SPECT examination fused with a CT scan (SPECT/CT), which increases the diagnostic value of the investigation. The aim of this paper is to evaluate the usefulness of 99mTc-DTPA SPECT/CT in diagnosing Graves orbitopathy, as compared with other methods. METHODS: Twenty-three patients with suspected active (infiltrative-edematous) Graves' orbithopathy were included in the study. Each patient underwent a CAS, an MRI, and a SPECT/CT. The obtained results were analysed statistically, with the assumed statistical significance of p < 0.05. RESULTS: The SPECT/CT and MRI were found to have the highest sensitivity: 0.93 each. The SPECT/CT had the highest specificity: 0.89. MRI and CAS had lower values: 0.78 and 0.56, respectively. The occurrence of an active form of GO had no impact on the exacerbation of exophthalmos or the thickness of the oculomotor muscles. CONCLUSIONS: The 99mTc-DTPA SPECT/CT method provides a very good tool for assessing the active form of GO and can, alongside the MRI scan, be used as a referential diagnostic procedure in GO.

Value of direct radionuclide cystography in diagnosing vesico-peritoneal fistulae.

A 36-year-old female patient underwent a laparoscopic surgery to remove a uterine fibroid. The procedure failed to relieve the pelvic pain, although its nature changed. After a period of observation, the patient was re-admitted to hospital on suspicion of a vesico-uterine fistula to be differentiated with endometriosis. Diagnostic investigations - cystography, cystoscopy, computed tomography and magnetic resonance - did not reveal a fistula. Laparoscopy was performed, with a possible biopsy in order to eliminate endometriosis. The result was negative, but chronic progressive reactive/inflammatory lesions were noticed, possibly indicating the presence of a vesico-peritoneal fistula. Therefore, a direct radionuclide cystography was performed. The scintigraphic images single-photon emission computed tomography (SPECT/CT) showed a radioactive spot, indicative of a vesico-peritoneal fistula. The fistula was treated for three months by catheterisation of the urinary bladder. The follow-up SPECT-CT did not reveal any urine leakage from the bladder. The clinical symptoms disappeared as well.

Calculation of therapeutic activity of radioiodine in Graves' disease by means of Marinelli's formula, using technetium (99mTc) scintigraphy.

The therapeutic activity of 131I administered to patients with Graves' disease can be calculated by means of Marinelli's formula. The thyroidal iodine uptake (131IUmax) needed for the calculation is usually determined with the use of 131I. The purpose of the paper was to estimate 131IUmax on the basis of technetium uptake in the thyroid at 20 min (99mTcU20min). Eighty patients suffering from Graves' disease were qualified for radioiodine therapy with measurement of fT4, fT3, thyroid-stimulating hormone and its receptor (TRAb). Prior to the treatment, all the patients were euthyroid. 131IUmax for each patient was determined according to the levels of 131I after 24 h (131IU24h), while effective half-life (T eff) according to the measurements of 131IU24h and 131I uptake after 48 h (131IU48h). Additionally, on the day before measuring 131IU24h, 99mTcU20min was calculated for each patient. It was demonstrated that there existed a correlation, with statistical significance at p < 0.05, between the following pairs of values: TRAb and 131IU24h, TRAb and 99mTcU20min, and 99mTcU20min and 131IU24h. The interdependence between 131IU24h and 99mTcU20min at the level of significance p < 0.05 is described by the following algorithms: 131IU24h = 17.72 × ln (99mTcU20min) + 30.485, if TRAb < 10 IU/ml, and 131IU24h = 18.03 × ln (99mTcU20min) + 38.726, if TRAb > 10 IU/ml. It is possible to predict thyroid iodine uptake 131IU24h in Graves' disease on the basis of measuring the uptake of 99mTcU20min. This shortens the time necessary for diagnosis and enables the calculation of 131I activity using Marinelli's formula.

Single, very low dose (0.03 mg) of recombinant human thyrotropin (rhTSH) effectively increases radioiodine uptake in the I-131 treatment of large nontoxic multinodular goiter.

BACKGROUND: Radioiodine therapy (RIT) in patients with large nontoxic multinodular goiter (MNG) recently becomes more common method in comparison to surgery (especially in elderly patients and with contraindications because of severe chronic diseases other systems). Repeatedly low thyroid radioactive iodine uptake (RAIU) decreases effectiveness of RIT or makes it impossible. The recombinant human thyrotropin can increase RAIU and improve the results of RIT. THE AIM OF THE STUDY: was to assess the influence of a single very low dose (0.03 mg) of rhTSH on RAIU and thyroid function in euthyroid (MNG-EU) and subclinical hyperthyroid (MNG-SC) patients with a large multinodular goiter. MATERIAL AND METHODS: 40 patients (14 male, 26 female, age 57-80 yr) with large non-toxic MNG over 80 grams and with baseline RAIU < 40% were included into the double-blind randomized study and divided into two groups: rhTSH-group and control group. First group received the single intramuscular injection of 0.03 mg rhTSH and the second received placebo. The RAIU were measured 24 and 48 hours after the rhTSH and then all the patients were administered therapeutic doses of I-131. TSH and free thyroxine levels were measured at 1st and 2nd day after the injection of rhTSH and later, at 4 and 8 weeks after the RIT. RESULTS: The mean RAIU increased significantly from 30.44 ± 7.4% to 77.22 ± 8.7% (p < 0.001). There were no statistically significant differences in RAIU between euthyroid (MNG-EU) and subclinically hyperthyroid (MNG-SC) patients. The peak of serum TSH was noticed 24 hours after rhTSH injection and in MNG-EU patients it has remained within normal range, similarly as fT4. In the MNG-SC group the administration of rhTSH resulted in a significant increase in the TSH values after 24 hours, whose mean level slightly exceeded the upper limit of the normal range with normalization at 48 hours. 8 weeks after the RIT, the TSH and fT4 levels did not exceed the normal range and did not differ in a statistically significant way. CONCLUSIONS: Even the single very low dose of rhTSH increases the values of RAIU in significant way, in euthyroid and subclinically hyperthyroid patients. The administration of rhTSH is well-tolerated. Neoadjuvant administration of a low dose (0.03 mg) of rhTSH before I-131 seems to be an optimal method of management which may increase the effectiveness of RIT and decrease the exposure of the patients to absorbed doses of ionizing radiation.

Radioiodine therapy for Graves' disease - retrospective analysis of efficacy factors.

INTRODUCTION: Radioiodine ((131)I) isotope therapy is the method of choice in the treatment of Graves' disease relapse. The efficiency of this method is dependent on many factors; therefore, the present paper aims to identify the parameters that have a crucial impact on the efficacy of radioiodine therapy for Graves' disease. MATERIAL AND METHODS: The authors performed a retrospective analysis of the medical documentation of 700 Graves' disease sufferers treated with (131)I. The patients were divided into three groups depending on the thyroid-absorbed dose of (131)I: group I - 100 Gy, II - 150 Gy, and III - 200 Gy. The authors assessed the influence of gender, age, presence of orbitopathy, TRab titres, thyroid mass, iodine uptake after 24 and 48 hours, and the absorbed dose on the treatment efficacy at one year post-(131)I administration. RESULTS: The volume of thyroid gland (P < 0.002) and the thyroid-absorbed dose (P < 0.001) were the only factors that had a significant impact on the outcome of the treatment. The likelihood of hyperthyroidism persisting (odds ratio: 3.71, 95% confidence interval: 2.4-5.87) was greatest in patients from group I. In group II, with thyroid volume amounting both to 25 mL and to 25-50 mL, the percentage of hyperthyroidism was lowest (1 and 0%). However, with thyroid volume > 50 mL, the percentage of hyperthyroidism was lowest in group III (10%). CONCLUSIONS: The absorbed dose of (131)I and the volume of the thyroid gland are two parameters that have a significant influence on the efficacy of radioiodine therapy for Graves' disease. 150 Gy is the optimal dose for glands < 50 mL. A goitre > 50 mL requires an absorbed dose of 200 Gy in order to minimise the risk of recurrent hyperthyroidism.

Parathyroid gland function after radioiodine ((131)I) therapy for toxic and non-toxic goitre.

INTRODUCTION: The therapeutic effect of radioactive iodine ((131)I) on benign goitre consists of the emission of tissue-destructive beta-radiation. Since the range of beta (131)I radiation in tissue can reach 2.4 mm, it can affect the adjacent parathyroid glands. The purpose of this paper is to assess parathyroid function in patients with toxic and non-toxic goitres, up to five years following (131)I therapy. MATERIAL AND METHODS: The study sample consisted of 325 patients with benign goitres (220 with toxic nodular goitre (TNG), 25 with non-toxic nodular goitre (NTNG), and 80 with Graves' disease (GD) treated with (131)I. The therapeutic activity of (131)I for each patient was calculated using Marinelli's formula. The serum levels of fT3, fT4, TSH, iPTH and Ca(2+), Ca and phosphates were determined one week before (131)I administration, as well as every two months up to a year following the therapy, and then after three and five years post-treatment. RESULTS: After two months following the administration of (131)I, all the treated patients showed a statistically significant above normal increase in iPTH concentrations (amounting to a value almost twice the norm in patients with TNG), which remained stable up to ten months after treatment, to return to normal level in the following months. In all the patients, Ca(2+), Ca, phosphates concentration remained within normal range throughout the course of the study. The concentrations of fT3 and fT4 quickly returned to normal after (131)I administration, and remained within normal range until the completion of the study. CONCLUSION: Radioiodine treatment of benign thyroid disorders results in transient (up to ten months after (131)I administration) hyperparathyroidism. The condition does not influence the level of calcium and phosphates concentration in any significant way.

Bone scan in metabolic bone diseases. Review.

Metabolic bone disease encompasses a number of disorders that tend to present a generalized involvement of the whole skeleton. The disorders are mostly related to increased bone turnover and increased uptake of radiolabelled diphosphonate. Skeletal uptake of 99mTc-labelled diphosphonate depends primarily upon osteoblastic activity, and to a lesser extent, skeletal vascularity. A bone scan image therefore presents a functional display of total skeletal metabolism and has valuable role to play in the assessment of patients with metabolic bone disorders. However, the bone scan appearances in metabolic bone disease are often non-specific, and their recognition depends on increased tracer uptake throughout the whole skeleton. It is the presence of local lesions, as in metastatic disease, that makes a bone scan appearance obviously abnormal. In the early stages, there will be difficulty in evaluating the bone scans from many patients with metabolic bone disease. However, in the more severe cases scan appearances can be quite striking and virtually diagnostic.

[Application scintigraphy in evaluation of salivary gland function]. / Zastosowanie scyntygrafii w badaniu funkcji gruczolów slinowych.

The salivary glands belong to the exocrine glands. There are tree main pairs of salivary glands: parotid, submandibular, sublingual. Several modalities are used for salivary gland imaging, such as sonography, computer tomography and magnetic resonance imaging. The aim of these methods is mainly to present morphological impairment. Parenchymal function and excretion function of all salivary glands can be quantified by scintigraphy. After single intravenous injection of 99mTc-pertechnetate sequential images are acquired up to 25-40 minutes. Usually about fifteen minutes postinjection 3 ml of lemon juice are administered intraorally as sialogogue. Salivary scintigraphy can estimate the severity of salivary gland involvement and function disorders, which may not be accurately reflected by the morphological damage. The clinical impact of scintigraphy has been reported in multiple salivary glands diseases, such as Sjogren's syndrome, sialolithiasis with or without parenchymal damage, iatrogenic irradiation of the salivary glands for therapy of head and neck tumors or radioiodine treatment of thyroid cancer. No other method can give so much information about function of salivary glands. Scintigraphy is noninvasive examination, easy to perform, reproducible and well-tolerated by the patient.

[The usefulness of nicotinamide in radioiodine therapy in patients with toxic and nontoxic large goitres]. / Uzytecznosc nikotnamidu w radiojodoterapii chorych z wolem nadczynny oraz dutymn wolem normoczynnym.

Nicotinamide (niacin) is very useful substance in treatment of many kinds of diseases. For the decades the main indications for application of niacin were lipid disorders. There are studies confirming that niacin increases thyroid radiosensitivity to 1-131. The radioiodine therapy is common method of treatment of hyperthyroidism (Graves' disease, toxic nodular goitre), large euthyroid goitre and differentiated thyroid cancer. In some studies with Wistar rats there is shown that niacin potentiates the effect of 1-131 by increasing thyroid blood flow, what results better effects of radioiodine treatment. Moreover niacin in therapeutic doses decreases serum thyroid hormone levels (mainly total thyroxine and thyroxine-binding globuline). In case of large goitre, when the calculated radioisotope dose exceeds ambulatory limits, the patient must be hospitalized. There are patients with low radioiodine uptake and radiosensitivity of thyroid, radiosensitizers can be utilized for this purpose. Recently obtained results of studies are showing that niacin can be used as radiosensitizer. It is making possible ambulatory treatment of patients with large goitres and low radioiodine sensitive thyroid. The radioiodine therapy with niacin could become shorter, less expensive and more safety for patients.